Problem: Express your answer as a mixed number simplified to lowest terms. $10\dfrac{4}{7}-4\dfrac{7}{8} = {?}$
Answer: Find a common denominator for the fractions: $= {10\dfrac{32}{56}}-{4\dfrac{49}{56}}$ Convert ${10\dfrac{32}{56}}$ to ${9 + \dfrac{56}{56} + \dfrac{32}{56}}$ So the problem becomes: ${9\dfrac{88}{56}}-{4\dfrac{49}{56}}$ Separate the whole numbers from the fractional parts: $= {9} + {\dfrac{88}{56}} - {4} - {\dfrac{49}{56}}$ Bring the whole numbers together and the fractions together: $= {9} - {4} + {\dfrac{88}{56}} - {\dfrac{49}{56}}$ Subtract the whole numbers: $=5 + {\dfrac{88}{56}} - {\dfrac{49}{56}}$ Subtract the fractions: $= 5+\dfrac{39}{56}$ Combine the whole and fractional parts into a mixed number: $= 5\dfrac{39}{56}$